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I think using QoS it would be easy to profile the user [fiber] channel if VRAD knew what exactly programs are playing at customer side. IPTV giving more to control such things, buffering at receiving side is the way to compensate low bandwidth allocation.

DIRECTV is just now attempting to use double the bandwidth that DISH has been using for a while now. Does the PQ difference bear this out or is it mostly a matter of comparing numbers instead of visual perception?

You've got to be kidding all of us.Why does Dish still reduce the 1080 resolution to 1440, "if" they have the bandwidth?

I think using QoS it would be easy to profile the user [fiber] channel if VRAD knew what exactly programs are playing at customer side. IPTV giving more to control such things, buffering at receiving side is the way to compensate low bandwidth allocation.

There may be several [many] way to improve this, "but" the fiber [or VRAD] isn't that smart. The fiber here connects to an Actel 48 port switch, where it's DSL to the customer.This is what they have to play with:

If you're too far from the VRAD, you can't get the band on the far right.[far left down stream, middle up stream, far right the second down stream]

DIRECTV is just now attempting to use double the bandwidth that DISH has been using for a while now. Does the PQ difference bear this out or is it mostly a matter of comparing numbers instead of visual perception?

DIRECTV is just now attempting to use double the bandwidth that DISH has been using for a while now. Does the PQ difference bear this out or is it mostly a matter of comparing numbers instead of visual perception?

Twisting my words? I meant he is commenting on picture quality without seeing it.

Measured at the U-verse gateway, AT&T's HD streams for video are approx. 5.7 Mbps. This makes sense as on the 32/5 U-verse profile (this is the one assigned to you on AT&T's fastest Internet speed offering, 24/3 Mbps) - one's Internet connection speed drops to 20 Mbps when viewing two HD channels at once - 14 Mbps when viewing 3 HD channels - and just 8 Mbps when viewing four HD channels. So yes, Internet speed loss on U-verse when viewing 2 or more HD channels definitely correlates with the 6 Mbps of bandwidth per HD channel as well.

The point of the comparison was to illustrate how bad AT&T U-verse looks at that bitrate - that a recording from Verizon FiOS of the same channel uploaded to YouTube still looks better than AT&T even after YouTube molests it. It's that bad.

As for whether or not DirecTV looks any worse with the 25% bitrate drop, I'd take opinions without some screenshots to back it up with a grain of salt. In the other thread about DirecTV HD channels the majority opinion is that the new channel they're adding, TCM HD - "looks great." This is despite the fact that it is the only high definition channel that has never aired a single minute of native high definition content. Most people are clueless when it comes to picture quality.

Really the only way to know scientifically is for a thorough identical frame screenshot comparison to be done like the AT&T vs. YouTube comparison above: screenshots need to be taken of a program before it gets dropped down to 6 Mbps and then a repeat of the program after the channel is dropped down.

No, they are saying that the Hi Definition version of Tcm will look better than the sd version of the channel, and there by will look great in comparison. They are correct about that, I don't know of a single show that doesn't look better on a Hi Definition channel than on a sd channel, regardless of if the show is in Hi Definition or not. DIRECTV compresses the heck out of their sd stuff any more.

And I just can't ever take anything on YouTube for any kind of comparison, sorry.

Also, many people have posted very wide ranging results about uverse depending on where they are, i don't care if it shouldn't make a difference or not. You don't know what's being done at the source in different places with those signals. Sat is the only source where all sources are treated identically everywhere.

And when I said compare, I mean with the Hi Definition channels that have already been moved to 6 per. I have not seen one person say they can tell. Not one.

This doesn't need to be a theoretical discussion. There are several high-profile channels that D* is already doing this with, and yet the DBSTalk community, which has many "PQ Hawks", hasn't raised a flag as of yet.

The content is out there. The burden of proof is on the doubters to bring in some evidence from the publicly available evidence. Let's see your screenies.

I'd be very surprised if engineers of the competition aren't trying very hard to punch holes in D*'s new methods. . .and would be more than happy to pass their results along, if they can find any smoking guns, to friendly surrogates in the online community. Try not to look shocked at the suggestion.

For some reason, I believe Xizer is here just to troll. Not quite sure if he really knows how DBS satellite works and what its capabilities are. Hell I don't know close to a quarter of it, but he just is here..... well, I actually really don't know why he is here.

[Disclaimer] The definition of "soon" is based solely on DirecTV's interpretation of the word, and all similarities with dictionary definitions of the word "soon" are purely coincidental and should not be interpreted as a time frame that will come to pass within a reasonable amount of time.

This doesn't need to be a theoretical discussion. There are several high-profile channels that D* is already doing this with, and yet the DBSTalk community, which has many "PQ Hawks", hasn't raised a flag as of yet.

I can't believe this "outrage", as it looks like a tempest in a teapot.

I started sorting through Sixto's map of TPs to figure out which channels were worth recording and then sorting out the bit-rates of the MPEG-4 streams, over time. In doing so, it seems fairly clear these TPs with more channels are due to the stat-muxing being tweaked a bit.
I've been watched many of these channels and if there is a problem with this many on one TP, it may be when the stat-mux "goofs", which could explain the moments of slight pixelation, as the peak MPEG-4 bit-rate gets limited.
I was on a DMA with 6 HD channels on one TP for a few years and with MPEG-4, it works.

If you've monitored MPEG-4 HD streaming, you know the bit-rates vary widely, from as low as 1 or 2 Mb/s, to a "general norm" of 7-9 Mb/s, to peaks in the 12-16 range.
What I see in the TP maps, is DirecTV optimizing their bandwidth usage.
I don't see any signs of "over compression" [been watching some of these channels], but suspect the weak point to be when the stat-mux can't allocate enough bandwidth for every channel's needed bit-rate, which might manifest as picture breakup for a few frames.
I might see this once or twice in a two hour movie.

Considering the work and effort to try to map out the bit-rates of all the channels on one TP, and then try to sync them in time to each other, it isn't worth it, when I expect this is exactly what the mux is doing.

I'd agree on AMC though. You can't just look at the quality coming to you, but what DirecTV gets to send out.

Yes AMC Networks statmuxes 4 HD channels together to be able to fit in one QPSK transponder or one 38.8mbps cable QAM channel. It's MPEG2 though so cable operators can just receive the whole package and translate it on one QAM frequency.

I've done a QAM analysis on Blueridge cable since their Passport software on a Cisco STB has a really thorough diagnostics mode. They run that same mux with the same vpid's and everything. It's like a direct translation from Galaxy 14 to a single 38.8mbps QAM. Not sure how DirecTV or others get this programming, but I don't think AMC wants to "encode it twice". That costs more money.

DIRECTV is just now attempting to use double the bandwidth that DISH has been using for a while now. Does the PQ difference bear this out or is it mostly a matter of comparing numbers instead of visual perception?

This reminds me of audiophile snobs. Their system sounds good because the numbers say it should. They don't listen to the music, but to the equipment.

I agree with this fro the most part, "but" the streaming from the DVR has been above 5.7 Mb/s.

Do you mean the streaming of recorded content, that was previously delivered at 5.7 Mbps?

I don't know the exact encoding U-Verse uses on its DVR, but a program in HD could be recorded on the DVR using a different type of compression, meaning the end-result on your hard drive is of such a format, that in order to stream it, it needs more bandwidth.

In THEORY, you can record the incoming TV stream into an uncompressed format, and you would end up with e.g. a 40 Gb file on your DVR for an hour show, which in turn, once played by a STB elsewhere, would require about 90 Mbps to play. That does not increase the quality though, it is just the way it was stored.

From that point of view, it would probably make sense that U-Verse (and any DVR actually) would store the incoming recording in a file compression method that does not compress the file any further, yet allows for quick play/access without too much CPU work.

U-verse DVR's have 320 Gb I think (some have 500). A portion is reserved for the OS, but you can probably calculate how much space a 1 hour show takes on your DVR, and in turn you can then calculate how much it would take to play it in Mpbs.

[Disclaimer] The definition of "soon" is based solely on DirecTV's interpretation of the word, and all similarities with dictionary definitions of the word "soon" are purely coincidental and should not be interpreted as a time frame that will come to pass within a reasonable amount of time.